Houseplant newbie here … I recently noticed a whitish sheen and some spots on a few of the leaves of my Living Lace Davana. I used the Dr. Planta diagnose function and it said the issue was dry air. Does that seem right based on the photo? Some of my own Dr. Google research unearthed the possible diagnoses of powdery mildew or water spots/calcium deposits. Really hoping it’s not powdery mildew... I try to mist regularly and I live in zone 7a. Thank you for any ideas/advice!